Hi, Michel -- welcome!
You shouldn't need to uninstall SilverKeeper, but if you've got it set up to do things on a schedule you might want to turn that off.
I don't know how to uninstall SilverKeeper, though: sorry... it might be in their documentation!
SuperDuper! is easy to uninstall. If you need to, you can just drag it to the trash. There are a few other files that are created at runtime, and all are described here:
http://www.shirt-pocket.com/forums/showthread.php?t=56
Hope that helps and -- once again -- welcome!